1. Technical Field
The present invention relates to an organic EL device, a method of manufacturing an organic EL device, and an electronic device.
2. Related Art
The organic electroluminescence device (hereinafter, referred to as an organic EL device) includes a stack of a positive electrode, an organic functional layer having at least a luminescent layer, and a negative electrode. For example, a top-emission type organic EL device is provided with a positive electrode or a reflection layer having optical reflectivity, so that the light generated from the luminescent layer is emitted to the negative electrode side.
In order to increase the luminance of the light emitted from the organic EL device, a method of amplifying and extracting the light having a resonance wavelength using an optical resonator for resonating the light from an organic functional layer included between a negative electrode and a reflection layer provided under a positive electrode has been proposed in JP-A-2006-339028 and JP-A-2007-220395.
In the method disclosed in JP-A-2006-339028, reflection layers corresponding to red, green, and blue colors RGB are formed in different layers, and insulation films are interposed therebetween. However, in such a structure, since the process of forming the reflection layer and the process of forming the insulation film are performed by three times for each R, G, and B colors, the number of manufacturing processes increases. In addition, since the reflection layer and the insulation film are arranged in three-layers between the positive electrode and the circuit portion, the contact hole may be lengthened so that risks such as bad connection may increase. On the other hand, in the method disclosed in the JP-A-2007-220395, the resonance wavelength of the optical resonator is adjusted by changing the layer thickness of the positive electrode according to the wavelengths of the colors R, G, and B. In such a configuration, it is possible to provide the reflection layer and the insulation film in a single layer.
However, in the method where the resonance wavelength of the optical resonator is adjusted by changing the layer thickness of the positive electrode, the layer thickness of the positive electrode is differentiated by combining, for example, three positive electrode layers. As a result, a portion where the layer thickness of the positive electrode is different is generated in a single area of the pixel. If the layer thickness of the positive electrode is different, the optical length of the optical resonator may change. Therefore, light beams of different resonance wavelengths may be mixed in a single area of the pixel. As a result, the luminance of the organic EL device may be degraded.